PI = 3.14
def hello_world():
    print('this is my first python program hello,world')


# get level
def get_level(score):
    if score >= 90 and score <= 100:
        return "A"
    elif score >= 80 and score < 90:
        return "B"
    elif score >= 70 and score < 80:
        return "C"
    elif score >= 60 and score < 70:
        return "D"
    else:
        return "不合格"

def is_circle(r):
    return PI * r * r
# find a good number
def is_good_number(x, y):
    # z = (x * y) % 2
    # print("this result is:", z)
    if (x * y) % 2 == 0:
        print("偶数")
    else:
        print("奇数")
def get_user_info():
    user_name = input("please enter your name:")
    user_age = input("please enter your age:")
    return user_name, int(user_age)